Marinate the fish with salt, lemon juice, turmeric powder and red chilli powder. Set aside for an hour.
In a separate bowl mix mustard oil, ginger paste and garlic paste.
Marinate the fish in the second marinade. Keep it for a couple of hours.
Heat refined oil on a tawa, when hot, add the marinated steaks one by one and cook evenly from both the sides till cooked and golden brown on both sides.